Malathion

Mechanism-of-action class: Cholinesterase Inhibitors.

• OVIDE Lotion is indicated for patients infected with Pediculus humanus capitis (head lice and their ova) of the scalp hair.ICD-10: B85.0

• OVIDE Lotion is contraindicated for neonates and infants because their scalps are more permeable and may have increased absorption of malathion. OVIDE Lotion should also not be used on individuals known to be sensitive to malathion or any of the ingredients in the vehicle.contraindicated

Apply OVIDE Lotion on DRY hair in amount just sufficient to thoroughly wet the hair and scalp. Pay particular attention to the back of the head and neck while applying OVIDE Lotion. Wash hands after applying to scalp. Allow hair to dry naturally - use no electric heat source, and allow hair to remain uncovered. After 8 to 12 hours, the hair should be shampooed. Rinse and use a fine - toothed (nit) comb to remove dead lice and eggs. If lice are still present after 7 - 9 days, repeat with a second application of OVIDE Lotion. Further treatment is generally not necessary. Other family members should be evaluated by a physician to determine if infested, and if so, receive treatment.

OVIDE Lotion is flammable. The lotion and wet hair should not be exposed to open flames or electric heat sources, including hair dryers and electric curlers. Do not smoke while applying lotion or while hair is wet. Allow hair to dry naturally and to remain uncovered after application of OVIDE Lotion. OVIDE Lotion should only be used on children under the direct supervision of an adult. If OVIDE Lotion comes into contact with the eyes, flush immediately with water. Consult a physician if eye irritation persists. If skin irritation occurs, discontinue use of product until irritation clears. Reapply the OVIDE Lotion, and if irritation reoccurs, consult a physician. Chemical burns including second-degree burns and stinging sensations may occur with the use of OVIDE Lotion. General Keep out of reach of children. Close eyes tightly during product application. If accidentally placed in the eye, flush immediately with water. Use only on scalp hair. Information to Patients OVIDE Lotion is flammable. The lotion and hair wet with lotion should not be exposed to open flames or electric heat sources, including hair dryers and electric curlers. Do not smoke while applying lotion or while hair is wet. The person applying OVIDE Lotion should wash hands after application. Allow hair to dry naturally and to remain uncovered after application of OVIDE Lotion. OVIDE Lotion should only be used on children under the direct supervision of an adult. Children should be warned to stay away from lighted cigarettes, open flames, and electric heat sources while the hair is wet.

Malathion has been shown to be irritating to the skin and scalp. Other adverse reactions reported are chemical burns including second-degree burns. Accidental contact with the eyes can result in mild conjunctivitis. It is not known if OVIDE Lotion has the potential to cause contact allergic sensitization.

Pregnancy Pregnancy Category B There was no evidence of teratogenicity in studies in rats and rabbits at doses up to 900 mg/kg/day and 100 mg/kg/day malathion, respectively. A study in rats failed to show any gross fetal abnormalities attributable to feeding malathion up to 2,500 ppm (~ 200 mg/kg/day) in the diet during a three - generation evaluation period. These doses were approximately 40 to 180 times higher than the dose anticipated in a 60 kg adult (based on body surface area and assuming 100% bioavailability). Because animal reproduction studies are not always predictive of human responses, this drug should be used (or handled) during pregnancy only if clearly needed.

Consideration should be given, as part of the treatment program, to the high concentration of isopropyl alcohol in the vehicle. Malathion, although a weaker cholinesterase inhibitor than some other organophosphates, may be expected to exhibit the same symptoms of cholinesterase depletion after accidental ingestion orally. If accidentally swallowed, vomiting should be induced promptly or the stomach lavaged with 5% sodium bicarbonate solution. Severe respiratory distress is the major and most serious symptom of organophosphate poisoning requiring artificial respiration, and atropine may be needed to counteract the symptoms of cholinesterase depletion. Repeat analyses of serum and RBC cholinesterase may assist in establishing the diagnosis and formulating a long - range prognosis.

• May 23, 2012ANDAANDA091559Suven Pharms

1. 1Drug Ineffective1212%
2. 2Pain1111%
3. 3Alopecia99.2%
4. 4Vomiting88.2%
5. 5Drug Exposure During Pregnancy77.1%
6. 6Dyspnoea77.1%
7. 7Pregnancy With Injectable Contraceptive77.1%
8. 8Thermal Burn77.1%
9. 9Burns Second Degree55.1%
10. 10Diarrhoea55.1%
11. 11Abdominal Pain44.1%
12. 12Application Site Burn44.1%
13. 13Application Site Scab44.1%
14. 14Application Site Vesicles44.1%
15. 15Blister44.1%

Recent PubMed references pinned to Malathion as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Pre-conception exposure to low doses of malathion during the juvenile and pubertal periods impairs placentation and offspring fetal development in female Wistar rats.
  Journal of developmental origins of health and disease · 2026 · Frigoli GF, Costa IR, Greghi JR, et al.
  PMID 42253212DOI 10.1017/S2040174426100580
• CRISPR/Cas12a-mediated electrochemiluminescent biosensor integrating Ag modified Co-doped metal-organic frameworks for dual detection of malathion and phorate.
  Analytica chimica acta · 2026 · Zhang Y, Liu W, Guo R, et al.
  PMID 41935011DOI 10.1016/j.aca.2026.345402
• Electrochemical/Colorimetric Dual-Mode Aptasensor Based on CuZr-MOF and Fe(3)O(4)@ZIF-8 for Detection of Malathion in Vegetables.
  Biosensors · 2026 · Liu K, Dong J, Wang Y, et al.
  PMID 41744720DOI 10.3390/bios16020101
• A dual-mode sensing strategy for the detection of Malathion based on bimetallic nanozymes coupled with aptamers.
  Talanta · 2026 · Nie L, Xu M, Yu H, et al.
  PMID 41633237DOI 10.1016/j.talanta.2026.129491
• Aggregation-induced emission coupled with dual quenching factor induced "on-off-on" electrochemiluminescence sensor for sensitive detection of malathion.
  Journal of hazardous materials · 2026 · Chen Y, Jiang D, Wang X, et al.
  PMID 41633145DOI 10.1016/j.jhazmat.2026.141300
• In silico investigation of acetylcholinesterase-insecticide interactions in Anopheles stephensi and Anopheles culicifacies using molecular docking.
  Journal of vector borne diseases · 2025 · Sha HC, Acharya S, Sahu B, et al.
  PMID 41568745DOI 10.4103/JVBD.JVBD_96_24
• Tissue-specific oxidative stress and protective interventions in malathion-induced toxicity in rodent models: A comprehensive review.
  Ecotoxicology and environmental safety · 2026 · Han D, Wen L
  PMID 41518979DOI 10.1016/j.ecoenv.2025.119607
• Highly Efficient and Selective Biosensing of Malathion Utilizing Bioengineered Nanoplatform Based on Fe(3)O(4).
  Langmuir : the ACS journal of surfaces and colloids · 2026 · Singh KR, Singh P, Pandey SS, et al.
  PMID 41500933DOI 10.1021/acs.langmuir.5c05560

The 10 most recently updated of 10 ClinicalTrials.gov registrations naming Malathion as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Impact of Community Scabies Treatment on Head Lice Prevalence in the Solomon Islands
  Completed · Phase 3 · Interventional · 118 enrolled · London School of Hygiene and Tropical Medicine
  NCT03236168updated 2019-06-14
• Pediatric Head Lice Study Product Comparison
  Completed · Phase 2 · Interventional · 97 enrolled · Hackensack Meridian Health
  NCT02213055updated 2016-07-29
• Safety and Tolerability of a Novel Malathion Formulation in Children Age 6-24 Months With Head Lice
  Completed · Phase 2 · Phase 3 · Interventional · 12 enrolled · Sun Pharmaceutical Industries, Inc.
  NCT00752973updated 2014-08-07
• Efficacy, Safety and Tolerability of a Novel Malathion Formulation in Patients 2 Years and Older With Head Lice
  Completed · Phase 3 · Interventional · 254 enrolled · Sun Pharmaceutical Industries, Inc.
  NCT00927472updated 2014-08-04
• Efficacy, Safety and Tolerability of a Novel Malathion Formulation in Patients 2 Years and Older With Head Lice
  Completed · Phase 3 · Interventional · 403 enrolled · Sun Pharmaceutical Industries, Inc.
  NCT00963508updated 2014-06-13
• Pharmacokinetics of Malathion Gel 0.5% and Malathion 0.5% Lotion (Ovide) in Patients With Head Lice
  Completed · Phase 1 · Interventional · 24 enrolled · Sun Pharmaceutical Industries, Inc.
  NCT00927407updated 2013-12-24
• Safety and Tolerability of a Novel Malathion Formulation in Infants and Toddlers With Head Lice
  Terminated · Phase 2 · Interventional · 30 enrolled · Sun Pharmaceutical Industries, Inc.
  NCT00291057updated 2013-12-23
• Safety and Efficacy of a Novel Malathion Formulation in the Treatment of Head Lice
  Completed · Phase 3 · Interventional · 360 enrolled · Sun Pharmaceutical Industries, Inc.
  NCT00244439updated 2013-12-23
• Ivermectin in the Treatment of Head Lice
  Completed · Phase 3 · Interventional · 812 enrolled · Johnson & Johnson Consumer and Personal Products Worldwide
  NCT00819520updated 2011-08-22
• Randomized Controlled Trial Comparing Efficacy and Tolerance of Four Pediculicides
  Completed · Interventional · 750 enrolled · Omega Pharma
  NCT00758823updated 2009-10-27

Frequently asked questions

How does Malathion work?

Mechanism-of-action class: Cholinesterase Inhibitors.

What is Malathion used for?

According to FDA labeling, Malathion carries indications including: OVIDE Lotion is indicated for patients infected with Pediculus humanus capitis (head lice and their ova) of the scalp hair.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Malathion?

Malathion is classified as Other ectoparasiticides, incl. scabicides, Cholinesterase Inhibitor, Cholinesterase Inhibitors, Increased Acetylcholine Activity.

What are the brand names for Malathion?

Malathion is marketed under brand names including Ovide.

What are the contraindications for Malathion?

Malathion labeling lists contraindications including: OVIDE Lotion is contraindicated for neonates and infants because their scalps are more permeable and may have increased absorption of malathion. OVIDE Lotion should also not be used on individuals known to be sensitive to malathion or any of the ingredients in the vehicle.. Always consult the full prescribing information and a clinician.